Sound distribution system



June 19, 1962 D. W. MARTIN SOUND DISTRIBUTION SYSTEM 3 Sheets-Shee'cl 1 Filed May 14, 1956 June 19, 1962 D. w. MARTIN 3,039,346

SOUND DISTRIBUTION SYSTEM Filed May 14, 1956 3 Sheets-Sheet 2 SWELL GREAT PEDAL E? PREAMP PRE-AMP PRE-AMP gl f23 /22 22| CROSSOVER CROSSOVER CROSSOVER NETWORK NETWORK NETWORK I L L 1 L E26 43 42 -***|4T{* I ErDcBA/SIFEDCEA! FEDcDA 0 0 0 O- I) O O O O 0 0 L r a5 [IT f4 'r 57'*- gg 54 I 0 0 0 l) U I I 53 52\ 7-L- L 93-L L L L L I 94 L89-L 5.9L @f2 52 QLMLLEVS? IMLI@ L LLLI34 55; [LE Ef( 'SS/fl( L 56 f eef E f leaf K lf l I 6 9 f f 60"' f f PROC. RIGHT 92! 97 96 LouD -SPEAKER l /96 88, OVERHEAD OVERHEAD OVERHEAD OVERHEAD EcHo LouD LouD I LouD L ouD LouD SPEAKER SPEAKER SPEAKER SPEAKER SPEAKER R9 #e l #7 #e *4 z -al E Lao l AMP A AMP L 78 j74-----J L77 I 76 j PEDAL ono-o o o. o4 o o -1I /BI o1 o-o o o1 o e o4 oooo- INVENTOR DANIEL W. MARTIN BY A 'ENT June 19, 1962 D. w. MARTIN SOUND DISTRIBUTION SYSTEM s sheets-sheet s I5 I8 "I Filed May 14, 1956 lLi /IQ 1 R 0 ,m f 0, w m I 3 V 4 5 N l ,A0 f, com. o L .92V 1 2 0k ,Ix/I HUA# .nw P A II P mK I` we m w M P mm ww coJ ou., mw s P 1| [[flxfI. EM o .M fl PP mw E 0| e 0 0 o if w m m5 f/L 42 EDK 7 7 95 O Hu 6 f/f L 6 2 ROM# A 2 M8 (/9 l /f/ D 4 56 f/ O f 6 W n A0 e r: 9 P RK B0 3 JL,... (rt 7 6 F- 4 um w c04/0L ,l mm 00 00070., E I SW 1( I) 2 )LLI T U V W X Vl Z n/ @M m o V www# w P RN E 9 w s ...u C F 0 J: .Ik 4 2 F 9 II I 0 ol II I I IIIIIII 9 o .I 5 D 6 MDM I o 3 7 2 A o EL Hume +V a 7 MNE# 8 P WK B 087 v w .I9IIL o I M VR C0 0.) 5: `1I IOI 0 00 b I II 2 6 E SW D( l 6 9 WR ST 6 3 I. SP OE E O 7 I 9 6 RN 8 9 A R w am R P c 3 F0 mow. ...om vom M 1 4 6 GUA3 HUK FUAZ A I I O 5 l0 n RO EOE I 0 RLn.. EL 5 LLP# .l IT. 5 A s w 0. 7 5 6 o 5 y. 4 5 6 rl. 1 5 66 6 m T R A M w. L E N A D a A. WILII w 5 .lx/ll m 7 /uI w n AGENT United States Patent O 3,039,346 SOUND DISTRIBUTION SYSTEM Daniel W. Martin, Newtown, Ohio, assignor to The Baldwin Piano Company, Cincinnati, Ohio, a corporation of Ohio Filed May 14, 1956, Ser. No. 584,609 Claims. (Cl. 841.08)

The present invention relates generally to acoustical radiation systems, and more particularly to acoustical radiation systems employed in conjunction with electric organs, and in which a plurality of acoustical radiators are controlled by a switching system, for the production of special acoustical effects.

In pipe organs the tones are radiated acoustically from the same devices which generate the tones. Consequently, it is feasible to have a tone of a particular pitch or timbre originate only from a single unique position in a room. In electronic organs the functions of tone generation and of tone radiation are separate and distinct. In general, the practice in electronic organ systems has been to combine the various tones generated electronically or electrically, and to radiate the combine-d tones acoustically `from one or more common locations by means of suitable electroacoustic transducers. This procedure possesses the advantage that the same tones which are available for radiation from any one location, such as the central part of the front of a church sanctuary, are also available at small additional cost for radiation from other locations, such as echo tone chambers in the rear of the sanctuary. In pipe organ practice, the production of tones from separated positions in a room would require great additional expense. However, the simple collection and distribution method of electronic organ tone production above referred to, which follows pipe organ practice, possesses an inherent disadvantage in that tones of different timbre cannot be radiated from different locations at the same time. For example, in one type of electronic organ in which design practice has leaned toward the tradi-tional pipe organ methods, complete independent tone generating systems are located in various positions relative to the listeners, and each tone generating system has its own separate tone radiating equipment. This procedure fails to take advantage of the flexibility of modern electronics, and often results in unnecessary expense-to the purchaser of electronic instruments. In accordance with the'present invention spatial and localization effects are produced Which are similar to those available from a pipe organ of great complexity, without requiring separate independent and complete loud speaker systems for each division of the organ console. Further, the present invention provides for unusual directional eifects, which are not feasible of production in pipe organs.

The production of good organ music requires delivery of a large amount of low frequency tone. Efficient radiators of low frequency power are of necessity large in size. Rigid wall construction is involved, which leads to relatively high cost. It is accordingly desirable to minimize the number of low frequency sources required in an organ system. It is known that low frequency tones are not readily localized by the human listener. The reason for this is that the wave lengths of low frequency tones are very large compared to the dimensions of the human head and the separation of the human ears, and because the phase difference at the two ears is therefore extremely small. Both ears receive low fre-v quency tones -at approximately the same amplitude and phase, which precludes binaural localization. This is not true of high frequency tones. It therefore becomes possible, by utilizing frequency-range dividing networks, and a relatively large number of small high frequency may lie within the range of 2002000 c.p.s.

loudspeakers together with a relatively small number of large low frequency loudspeakers, to provide a system having versatility far beyond the limitations inherent in pipe organ system design. Briefly, directional and 1ocalization effects are accomplished by properly locating a plurality of relatively high frequency speakers, While the required low frequency acoustic power is radiated from a single high power and high eiciency source.

Because the organist naturally divides the musical effects which he produces into three categories, on the basis that they are produced in response to activity of the left hand, right hand and feet, it is desirable in electronic organ systems to retain this type of separation. However, it is neither necessary or desirable to make this the only basis of division, `as has been the practice in the past. In accordance with my invention it is possible to provide a traditional type of distribution of production of musical effects, in combination with frequency range division, with attendant advantages of increased ilexibility of organ effects, including localization, and with concomitant greatly reduced cost of equipment.

In order to obtain division of the conventional type, i.e. pedal, great and swell, one may, according to the Ypresent invention utilize separate preampliers for the outputs of the three corresponding groups of tone color filters of the electric organ, or at least three separate channels. Each channel may be subject to separate pedal or manual volume control, vibrato, timbre control, or other types of control or modulation. After these controls and effects have been added, each group of tone signals passes through a cross-over network having a cross-over frequency of the order of 40() c.p.s., although the present invention is not limited to this precise frequency or `order of frequencies, and the crossover point Signals from the low-pass sections of the cross-over networks are combined and transmitted to a central efficient tone radiation system. This system might consist of one or more low frequency horns, with suitable horn extensions for maximum response at extremely low frequencies, or it may consist of groups of large direct radiation lou-d speakers on hafes, depending upon the nature of the -installation involved and the cost limitations which exist. Horns would be used where maximum performance was desired, or where space limitation prevented the use of large baifles and multiple speaker units. The outputs of the highpass sections of .the various cross over networks are connected to a gang selector switch. By means of the gang selector switch it is possible to obtain a wide variety of spatial effects, specific examples of which are described hereinafter.

Describing ybriefly the tone radiation systems which are connected to the output terminals of the Vselector switch, I employ tone radiators, each consisting of one or more loudspeakers capable of transmitting sound efficiently only primarily in the frequency range above the cross-over frequency. I install these tone radiation systems at various positions throughout a church sanctuary, as `dictated by musical and liturgical requirements. These high frequency systems may consist of single efficient horn type units, or groups of less efcient direct radiating loudspeakers, perhaps of 8" size, which can be installed at relatively low cost in very small spaces, as compared with full-range loudspeaker inclosures conventionally utilized. In churches and auditoria where troughs are used for in direct lighting, small loudspeaker inclosures could be situated in the troughs in a completely concealed manner. The use of overhead music is extremely effective in religious services, and this is an advantage of electronic organs over pipe organs since in pipe organs it is impractical to provide overhead music because of Weight, size and cost factors while in electronic music` the location of relatively small loudspeakers overhead presents no difficulty. Furthermore, by the inclusion of suitable reverberation means, employing different time delays for different output channels, the multiple overhead loudspeakers may assist greatly in providing distribution in space as well as in time, to the reverberation effects.

Location of the low frequency sound radiation system is not critical, and it may be centrally located, or located on the left or right of the front part of an auditorium. This does not imply that the location is unimportant, because it is well known that corner locations for low frequency sound sources are to be preferred, especially in small and medium-size rooms.

Through the centralization of the radiation of low frequency tone and the wide distribution of high frequency loudspeakers, great flexibility of control of the apparent sound source or sources is gained at minimum cost. It appears to the ear of the listener that the sound originates from that direction from which the high frequency cornponents arrive, in the absence of directional effects associated with the low frequency tones.

Outlining now some of the effects which may be obtainable in systems arranged in accordance with the present invention, when the Speaker selector switch is in a position designated A for purpose of identification, and representing a first position, the output of the swell division of the organ may seem to come from the left and that of the great division from the right. Actually, the low frequencies would be radiated from a central position, or from both left and right, depending upon the specific installation. The low frequency power for the pedal tones would be produced in the most efficient manner, while the high frequency components of such pedal tones as the contrabassoon and cello would be radiated from either left or right high-frequency loudspeaker locations, as determined by the wiring selected for a particular installation, or could be radiated from a separate high-frequency loudspeaker in a central location. Accordingly, position A of the selector switch provides a traditional effect, i.e. that produced by the physical separation of the swell and great organs.

For a second or B position of the selector switch, the entire organ might appear to be located overhead, despite the fact that the heaviest and largest part of the system would be at or near floor level. The apparent overhead location of the sound has obvious application in religious symbolism for such uses as prayer accompaniment. For a third or C position of the selector switch, the swell and greatlorgan facilities may be transported to the rear of the auditorium by means of echo loudspeakers. The `sound of the echo organ may be made audible in the church vestibule, and at such other remote locations as those where a choir is located for performance of opening and closing musical selections and response.

In further positions of the switch, further relative locations for the great and swell divisions of the organ may be provided.

As an additional feature of the present invention, a central directional high frequencyhorn may be included, which is used in conjunction with a solo stop selector switch. Some organ stops are intended primarily as solo stops, while others are utilized chiefly for building ensemble. Still others serve dual purposes. In the pipe organ the output from a bank of pipes, and the manner in which this output is radiated acoustically, is Xed by the particular manner in which the pipes are designed and installed. In an electronic organ system, this need not be the case. Tone color may be reproduced at various levels relative lto the overall organ tone and it may be radiated in a variety of highly directional and highly non-directional ways. It may be an advantage musically, for example, to call special attention to a particular musical voice. By means of a solo-stop selector switch it is possible to select any one of the solo stops available in an electronic organ, independently of usage in the ensemble, to effect an efficient directional and authoritative presentation via the directional high frequency horn.

While the possibilities ofthe present system of electronic organ music production have been discussed lhereinabove in terms of selection of apparent locations of tone sources, in various combinations, it is `further possible to arrange for useful time and space sequences of selection. Accordingly, I provide a processional switch under either manual or pedal control, which produces either moving or accumulative sequences which are spatial. For example, sounds of low volume may be caused to emanate from the rear of an auditorium, and volume may be added to the tone both in level and apparent size, until finally all of the amplification resources are brought into operation. Such an accumulative sequence would be particularly useful in connection with processional and recessional activities in church services. Other sequences, both of individual acoustical sources or groups thereof, or moving or accumulative sequences such as described immediately above, can be provided to meet particular local or denominational purposes, in response to simple changes in wiring of the processional switch.

It is accordingly a broad object of the present invention to provide a novel system of organ tone production, having great flexibility of spatial and combinatory effects.

It is a further object of the present invention to provide an organ tone system in which solo stops may be made to appear as emanating from a. particular described direction in a church, independently of the diffused nondirectional tone radiation effect of the organ, as a whole.

It is a further object of the invention to provide an electronic organ control system in which any combination of consoles or any single console may be caused to control tones emanating apparently from any desired location or combination of locations in a room, by actuation of a switching arrangement.

Still a further object of the present invention resides in the provision of an electronic organ system in which low frequency tones generated by any division of the organ are all radiated from one or more locations by means of a relatively high eiciency low frequency acoustic radiator system, while the high frequencies alone are radiated in accordance with a selective spatial or time sequential arrangement.

The above and still further features, objects, and advantages of the invention will become apparent upon consideration of the following detailed description of a specific embodiment thereof, especially when taken in conjunction with the accompanying drawings wherein:

FIGURE 1 is a schematic and block diagram of the essential elements of a system in accordance with the present invention;

l FIGURE 2 is a schematic and block diagram illustrating lcertain features of FIGURE l in detail and extending that figure in certain respects;

FIGURE .3 illustrates a modification of FIGURE 2; and

FIGURES 4 and 5 illustrate in details two forms of gradual switching devices employed in the systems of FIGURES 1-3, inclusive.

Referring now more particularly to FIGURE 1 of the accompanying drawings, there is illustrated, largely in the form of a block diagram, various of the generic features of the present invention. FIGURES 2 and 3 illustrate, respectively, two specific forms of the invention of FIGURE l, lbeing restricted to those features of FIG- URE 1 which are only generically indiacted in the latter gure. The reference numeral 10` denotes an array of stop switches in the console of an electric organ, having the general character of that disclosed in U.S. patent to Jordan, No. 2,555,040. Resistive isolation networks, conventionally illustrated at 11,V enable ythe abstraction of selected tonesfor application via leads 13 to a singlestop selectionV switch 14, independently of the conditions of the several stop .switches 10. Closure of selected ones of switches 1t) enables application of selected combinations of tones, deriving from the pedal, great and swell divisions of the organ, over leads 15, 16 and 17 to separate pedal, great and swell preamplifiers, respectively identified by reference numerals 18, 19 and 20. Accordingly, four distinct channels are available to the instrument, one deriving from selector switch 14, and which carries a solo stop, selected from one of the organ divisions, and the remaining three channels carrying combinations of stops deriving separately from the pedal, great and swell divisions of the organ.

The pedal pre-amplifier 18 is connected in cascade with a cross-over network 21, the great pre-amplifier 19 with a cross-over network 22, the swell pre-amplifier 2i) with a cross-over network 23 and selector switch 14, with a cross-over network 25. A pre-amplifier 24 may be inserted between the switch 14 and the cross-over network 25, if desired. The several cross-over networks 21-23 and 25 may be designed for the same or for slightly different cross-over frequencies, at .about 40:0 c.p.s., although I do not desire to be limited to values of cross-over frequency at or adjacent to 4010 c.p.s., values in the range ZOO-2000 c.p.s. being quite satisfactory in practice.

Each cross-over network has two output channels 26 and 26a, as is conventional, the channel 26 for relatively low frequencies and the channel 26a for relatively high frequencies. The several low frequency channels 26 are' all connected in parallel to the movable contact of a multi-position selector switch 27 having six stationary contacts, respectively designated A-F. The several stationary contacts A-C, E and F are each connected through a distinct attenuator pad 28 (conventionally illustrated) to a common output lead 29, while the stationary contact D is connected directly to the lead 29, without the interposition of a pad. Each of the attenuator pads 28 provides a predetermined attenuation of the signals appearing on the leads 26. No attenuation is provided when the movable contact engages the stationary contact D. v

The signal on output lead 29 is .applied via a power amplifier 30 to a high-efiiciency, high power radiator system of large size, conventionally illustrated as a single low frequency horn 32. The power amplifier 30 includes a mechanically actuated volume control 31, which, as will become apparent as the description proceeds, controls the power output of the amplifier 30 during operation of the system to obtain processional effects. Although the radiator system is illustrated as comprising a single low frequency horn 32, it may in fact consist of one or more horns, or one or more loudspeakers, depending on the nature of the installation, on cost limtations, and the like. The radiation system exemplified by horn 32 is the sole low frequency radiation system employed. It is known that low frequency tones are not readily localized by the human listener, so that the location of the radiation system 26 may be selected in accordance with acoustical and economic or .architectural considerations.

The high frequency output of cross-over network 25 is coupled via lead 33, switch 34, and power amplifier 35 to high-frequency directional horn 36. Accordingly, that stop which is selected by solo-stop selector switch 14 is radiated by the low frequency radiation system 32 and -by the high frequency directional horn 36. There results an apparent localization of the selected tone, since the apparent source of a tone lies in the direction of radiation of its higher frequency components, and the directional horn yields a high ratio of direct to reflected sound at the listener. The switch 34 in the lead 33 to the high frequency directional horn 36 allows a public address system, comprising microphone 37 and preamplifier 38a to be coupled at will to the high frequency horn 36. The switch 34 may be positioned at the pulpit, thereby allowing a speaker selectively to couple the horn 36 to the micro- 6 phone 37 during announcements or sermons, and to the organ during musical intervals. Since the switch 34 is effective to disconnect only the horn 36 from the organ, background organ music may be provided during the rendering of sermons, etc., over the remaining loudspeakers of the system.

The high frequency channels 26a of pedal cross-over network 21, great cross-over network 22., and swell crossover network 23, are coupled via leads 38, 39 and 40, respectively, to ganged movable arms of selector switches 41, 42 and 43 each of which includes a movable arm and a plurality of stationary contacts, identified by the letters A-F, respectively. The movable contacts of the switches 4-1, 42 and 43 are also `ganged -with the movable contact of the switch 27, so that the particular attenuator pad 28 connected between leads 26 and lead 29 is determined concomitantly with the settings of the switches 41, 42, and 43. The stationary contacts of the switches 41 to 43 provide various predetermined interconnections between the leads 26a and a plurality of high frequency sound radiators. The stationary contacts D, of the several selector switches 41, 42, 43, for example, may all be connected via the common lead 44 to a movable arm 45 of a multiple wafer selective switch 46, schematically illustrated, and denominated a processional switch, because of the aesthetic effects which its operation provides. The latter includes a plurality of stationary contacts 47 designated by the letters T-Z. The movable arm 45 of processional switch 46 may be pedal actuated, as by pedal 48, or may be manually actuated, and may include a contact 49 capable of |bridging two of the stationary contacts 47, in order to avoid discontinuities of musical effects during circuit selection by the pedal 48. AIt will be apparent, then, that when the movable contacts of switches 41, 42 and 43 assume the D position, the processional s-witch 46 assumes control of tone routing in response to actuation of pedal 48, but that for all other switch positions the processional switch 46 is inactive. The pedal 48 is coupled via mechanical coupling 50 to the volume control 31 of power amplifier 30 and, consequently, when the switches 27, 41, 42 and 43 are in terminal position D, and the pedal 48 is actuated, the power output of the amplifier 30 is controlled by the pedal 48, while in all other positions of the switches 27, 41, 42 and 43 the nominal power input and, therefore, nominal power output of the amplifier 30 is determined solely by the attenuator pads 28, since the pedal 48 remains unactuated. It will be obvious, however, that the input and output of the power amplifier 30 is variable, as desired by the organist, when controlled by suitable expression controls 114, connected, as shown, between the preamps and cross-over networks of each organ division.

Referring now additionally to FIGURE 2 of the accompanying drawings, there is illustrated one specific arrangement of interconnections between selector switch positions and plural loudspeakers, and one specic arrangement of a multiple wafer processional switch together with exemplary connections therefrom to an array of relatively high frequency acoustic radiators, which serves to clarify and extend the material illustrated in FIGURE l.

It is assumed, for the sake of example only, that one or more high frequency sound radiators (#2) are located on the lef't of a church sanctuary, and a similar array (#3) at the right. Four high frequency sound radiator arrays are located overhead, and are distributed rearwardly of one another. These are identified as radiators #6-#9. A high frequency echo loudspeaker (#4) is located rearwardly of the church, vwith a port to the vestibule. This arrangement lends itself well to Protestant services, but the placement and number of sound1 radiators may be appropriately modied for other religious denominations.

The selector switches 41, 42 and 43 are conventionally represented as multiple wafer switches having two wafers per switch so that the various combinations of loudspeakers, as set forth below, may be selected by the different switch positions. Additional wafers or contacts per wafer may be added to each switch in order to provide greater freedom in selection of the Various loudspeakers.

All of several output terminals A to F of selector switches 41, 42 and 43 are not utilized in the specific application Vof my invention illustrated in FIGURE 2 of the accompanying drawings, as might be the case in a more complete installation. Specifically, referring to the terminal connections illustrated in FIGURE 2, the swell selector terminal A is connected via leads 51 and 52 and amplier 52' to the left loudspeaker #2, While the pedal and great selector terminals A are connected respectively over leads 53 and 54 to a common lead 55 and via lead 55 and amplier 56 to the right loudspeaker #3. The terminals B of the swell, great and pedal divisions are connected respectively over leads 57, 58 and 59* to a single lead 60 and via lead 60 to a lead 61. The lead 61 is connected to a junction of four leads 62, 63, 64 and 65, the leads 62, 63, 64 and 65 being connected, respectively, via leads '72, 73, 74 and 75, to the input circuits of power amplifiers 76, 77, '78 and 79. The power ampliers are connected, respectively, over leads 80, 81, S2 and 83 to the overhead loudspeakers #6-#9. Thus, selector position B connects all divisions of the organ to the overhead loudspeakers #6-#9, simultaneously. Each of the leads 62, 63, 64 and 65 contains a set of stationary contacts 66 of a single-throw, four pole switch 67. The movable contacts of the switch 67 are ganged and operated by a relay 68 which, when energized, opens the switch 67 and breaks the parallel connection of the leads 62, 63, 64 and 65. Energization of the relay 68 is controlled by a multiposition switch 69 having a movable contact, ganged with the movable contacts of switches 41, 42 and 43, and six stationary contacts designated by letters A to F, corresponding to the contacts A to F of switches 41, 42 and 43. Contact D of the switch 69 is connected over lead 70 to the relay 68, all of the other stationary contacts being unconnected. The movable contact of the switch 69 is connected over lead 71 to a source of energizing voltage (not illustrated) so that when the switches 41, 42 and 43, and consequently switch 69, are in position D, the relay 68 is energized, thereby opening the leads 62, 63, 64 and 65.

In selector position C the pedal division is connected to the left and right loudspeakers #2 and #3 simultaneously. Contact C of the upper wafer of switch 41 is connected via leads 84 and 52 and amplier 52 and thence to loudspeaker #2. Contact C of the lower wafer of switch 41 is connected to contact A of the same wafer and via leads 53, 55 and amplifier 56 to the right loudspeaker. The great and swell divisions of the organ in selector position C are connected to the echo loudspeaker #4 via leads 86 and 87, connected respectively to the lower C contacts of switches 42 and 43. The leads 86 and 87 are connected via a common lead 88 and an amplier 88 to the loudspeaker `#4 which may be located to have an aperture adjacent the church vestibule.

For selector positions D, all divisions of the organ are simultaneously connected to the multiple wafer processional switch 46, the operation of which will be explained in detail hereinafter. To this end, the selector contacts D of the switches 41, 42 and 43 are connected respectively via leads 89, 90 and 91 to a single lead 92 and via lead 92 to the switch arm 45 of the processional switch 46. In selector positions E the pedal and great divisions of the organ are connected to the left and right loudspeakers #2 and #3, simultaneously, while the swell division is connected to overhead loudspeakers #6-#9. The contact E of the upper wafer of the pedal selector switch 41 is connected via leads 84 and 52 to the left loudspeaker #2 and the E contact of the lower wafer of the selector switch 41 is connected via leads 53, 55 and amplier 56 to the right loudspeaker #3. The E contact of the upper wafer of the great selector switch 42 is connected via leads 85, 52 to the left loudspeaker #2 and the contact E of the lower wafer of the great selector switch 42 is connected via leads 93, 55 and amplifier 56 to the right loudspeaker #3. The E contact of the swell selector switch 43 is connected via leads 57, 6i), 61 to the leads 62, 63, 64 and 65 hence through the circuit previously traced to the overhead loudspeakers #6-#9. In selector positions F the swell and pedal divisions are connected to echo loudspeaker #4 and the great division is connected to the left and right loudspeakers #2 and #3 simultaneously. Contact F of the pedal selector switch 41 is connected via leads 94 and 8S to the echo loudspeaker #4. The contact F of the upper wafer of the great selector switch 42 is connected via leads 85 and 52 to the left loudspeaker #2 and contact F of the lower wafer of the great selector switch 42 is connected via leads 93, 55 and amplifier 56 to the right loudspeaker #3. Contact F of the swell selector switch 43 is connected via leads 87 and 88 to the echo loudspeaker #4.

The directional effects obtainable7 by virtue of the speciiic arrangement recited, are as follows:

Switch position: Eect A Swell on left; pedal and great on right. B Entire organ overhead.

' C Swell and great on echo, pedal in front.

D Processional. E Great in front, swell overhead, pedal in front. F Swell and pedal on echo, great in front.

The switching provisions `are sufficiently flexible to enable inthe-eld modifications of the recited arrangement, to suit various types of services, and of building architecture, the described switching sequence being only one of many which may be employed. All of the loudspeakers #2, #3, #4 and #6 to #9 are relatively high frequency transducers and, therefore, may be of relatively small size and readily installed in concealed locations if desired.

The processional switch 46, in one preferred embodiment of my invention, is a multiple wafer switch, conveniently illustrated in FIGURE 2, having a separate wafer for each of loudspeakers #2 to #4 and #6-#9, so that any combination of these loudspeakers may be selected for any one of the switch positions, by suitably interwiring the several wafers. The switch arms 45, illustrated as a single arm to simplify the drawings, are in fact seven ganged switch arms, each selectively engageable with the contacts 47 of a different wafer.

The switch 46 is utilized to select any horizontal array of the stationary contacts `47 and applies thereto in parallel the relatively high frequency output of the several organ divisions. The contacts `49 of movable arms 45 may be so designed that they may momentarily make contact with two vertically adjacent contacts simultaneously, while in process of transfer, to prevent audible gaps in reproduction. The seven wafers ofthe switch '46 are designated by the numerals l to 7 (located in the drawings immediately above each vertical column of the contacts `47) and the positions of the switches are designated by the letters T-Z (located to the left of the horizontal rows of contacts 47). The contacts of wafer l of the switch 46 are `all connected together and via a lead 95 to the lead `88, and thence via amplilier 88 to the echo loudspeaker #4. The Y and Z contacts of the second wafer of the switch 46 are connected together and via leads 96, 5.2 and amplifier 52 Ito the left loudspeaker #2. Contact Z of the third wafer is connected via leads 97, 55 and amplifier 56 to the right loudspeaker #3. The U-Z contacts of the fourth wafer switch Y46 are connected together and via lead 72, power amplifier 76, and lead y to the overhead loudspeaker #6. The V-Z contacts of the fit-th wafer of switch 46 are connected together and via lead 73, power amplifier 77 and lead'81 to the overhead loudspeaker #7. The W-Z contacts of the sixth wafer are connected together and via lead 74, power amplifier '78, and lead 82 to the overhead loudspeaker #S. The X--Z contacts of the seventh wafer of the switch 46 are connected together and via lead 75, power amplifier 79 and lead S3 to the overhead loudspeaker #9.

The interconnection of the contacts of the various wafers l-7 of the switch 46 and the loudspeakers provide for the gradual lling of an auditorium with sound starting at the rear of the auditorium and sequentially energizing each of the overhead loudspeakers beginning with the rearward-most loudspeaker, and finally energizing the left and fright loudspeaker #I2 and #3, lo-

cated at the front of the auditorium. The movable contacts `49 of the switch 46 initially engage all of the contacts l47 in the T position of the wafers in which position only the lecho loudspeaker #i4 is energized. The sequence of sound channeling as the pedal `48 is depressed to progress the movable contacts 49 downward is as follows:

Switch Position: Loudspeakers active T 4 U 4, 9 V 4, 8, 9 W 4, 7, 8, 9 X 4, 6, 7, `8,9 Y 2, 4, `6-9 Z 2, 3, "4, 6-9

Unless provisions were made for opening the parallel connection of the leads 62-65, energization of one of the overhead loudspeakers 6-9 would produce energization of all of these transducers. Thus, ifa signal appeared on the lead 72, it would proceed via lead 62, the junction of the leads 62 through `65, through these leads to the remainder of the overhead loudspeakers. Therefore, the switch 67, relay coil 68 and selector switch 69 are yincluded in the apparatus of the present invention to open this parallel connection and allow selective energization of the loudspeakers #6 through #9 when the switches 41, 42 and 43 are in the terminal D position; that is, when the organ is placed under the control of the processional switch 46.

As previously indicated the contacts 47 of each horizontal array of contacts are'connected through the separate power amplifiers 76-79 to the input of the various loudspeakers #6-#9. As a result of the progressive energization of the transducers, the total energy level of the radiated high frequency components is progressively increased. In order to maintain a proper energy rel-ationship between high and low frequency components of the music,.the power amplifier 30, connected in circuit with low frequency loudspeaker 32, is provided with a volume control 31, operation of which is effected by the pedal 48. As the pedal is depressed progressively to energize loudspeakers #2-#4 and #i6-#9, the power output of power amplifier 3() is progressively increased, by means of gain control 31, to maintain the proper energy relationship between high and low frequency components. The variable gain control 31 provides control over the output energy of the loudspeaker 32 when the pedal 48 is depressed, which normally occurs when switches 41-43 are in switch position D, that is, when processional effects are desired. In order to provide control of the relative energies of the high and low frequency components of the music for the other positions of switches 41 to 43', the attenuator pads 28 are selectively inserted in the input lead 29 to the power amplifier 30.

The total energies of the radiated high frequency components ofthe music vary considerably with the position of the switches 41 to 43. For instance, when the switches 41-42 are in selector position A, only two loudspeakers, #2 and #3, are energized, whereas, when the switches are in selector position E, all the overhead loudspeakers #I6-#9' and both of the front loudspeakers #2 and #3 are energized, making a total ofvsix active transducers as opposed to two active transducers in selector position A. 'Ihe attenuator pads 28 are designed to compensate for the number of high frequency loudspeakers active in any given selector position, so as to maintain the predetermined energy relationship between high and low frequency components. The particlar energy relationship chosen depends upon the auditorium in which the organ system of the present invention is to be installed It may be desirable to maintain equality between the energies of the high and low frequency components, or some other relationship may be found desirable in a particular installation. Once this energy relationship has been determined the attenuations of the various attenuator pads may be selected and inserted in the system. If, thereafter, it becomes desirable to change the energy relationship, this may be accomplished lby changing values of attenuator pads 28. The volume control 31 which controls the energy relationship of the high and low frequency components of the organ during processional effects may provide the same or different energy relationships when the processional switch 46 is active. The precise control provided by the gain control 31 maybe determined by the taper of the control, or by other well known techniques.

Other moving or -accumulative sequences, both of individual acoustical sources or of groups of sources, may be provided by switch lwiring modifications, to meet particular local or denominational purposes. A specific arrangement of switching circuits wherein music is initiated at the rear of the church and advances forward to a localized position at the front of the chuch, is illustrated in FIG- URE 3 of the accompanying drawings. The embodiment of the invention illustrated in FIGURE 3 of the drawings is generally similar to the embodiment illustrated in FIGURE 2, and the same numerals of reference are accordingly applied to corresponding parts in the two figures.

The channelling of the frequency components of various divisions of the organ when the switches 41 through 43 are in terminal positions A-C, E and F are the same as illustrated and described in connection with FIGURE 2. The only change in this portion of the circuit is that the separate power amplifiers 76-79` for each of the overhead reproducers #6-#9 have been replaced by a single power amplifier 98, inserted in the lead 61 between the lead 60 'and the junction of the leads 62 through 65. The utilization of a single power amplifier 98 as opposed to separate power amplifiers 76 through 79 for each of the overhead loudspeakers #6-#9 reduces the cost of the system, but also reduces the total power output obtainable from the four overhead transducers. The latter effect may be desirable when systems in accordance with the present invention 4are utilized in small auditoria, and whether to utilize a single amplifier rather than fourseparate amplifiers for the overhead transducers will generally be determined by the size of the auditorium, and by allowable cost factors.

Proceeding with the description of the embodiment of the invention illustrated in FIGURE 3, selector position D of the switches 41, 42 and 43 couples the various divisions of the organ over lead 92 to selector arm 45 of the processional switch. In the presently described modification of the invention, the processional switch designated by reference numeral 46 is -a switch having a total of two wafers, and seven contacts per wafer. The wafers are designated by the numerals l and 2 (disposed vertically above each vertical column of contacts 47, in FIGURE 3) and the various contacts of each wafer are designated by the letters T through Z (at the left of the horizontal rows of the contacts). The contact T of the first wafer is connected over leads 95 and 88 and through amplifier 88 to the echo loudspeaker 4 and the contacts U through X are connected respectively over leads 72, 73, 74, 75,

l. 1 to the loudspeakers #6, 7, 8 and `9 while the contacts Y land Z are connected respectively over lead 96 and amplifier 52' and leads 97, 55 and amplifier 56 to the loudspeakers #2 and #3. Only one contact, Contact Z, of the second Wafer is connected and it is connecte-d over lead 99 to lead 96 to the left loudspeaker #2. The two movable contacts 49, only one of which is illustrated in FIGURE 3, are controlled by the pedal 4S and are initially positioned to engage the contact T of the first and second wafers. A single power amplier, 100, is inserted in the lead 92 between the terminals D and the switch -arm 45 and is utilized to replace the separate power arnplfiers 76 through 79` for each of the loudspeakers #6-#9 when the electric organ is utilized to provide processional effects. In this embodiment of the invention, selective switching of the loudspeakers #6-#9 occurs in the output circuit of a single power amplifier, as opposed to selector switching in the input circuits of power amplifiers 76 through 79, employed in the embodiment of my invention illustrated in FIGURE 2. Where selector switching is provided in input circuits of power amplifiers, a separate amplifier must be employed for each transducer and, consequently, the overall acoustic power output is greater than in a system employing a single amplifier. Either type or both types of switching may be utilized in a given system, depending upon the acoustical power required, cost limitations and the like. The position of the selector arm 45 is controlled by the pedal 48, the contacts 49 initially engaging the T contacts of the first and second wafer. Therefore, the echo loudspeaker #4 is initially energized and as the pedal is depressed the contact 49 sequentially and successively engages the contacts U through Z. Thus, the music is initially produced at the rear of the auditorium or church and proceeds forwardlythrough overhead loudspeakers #6-#9, to the left loudspeaker #2, and then to the left and right loudspeakers #2 and #3. The sequence of sound channelling for the several switch positions is as follows:

Switch position: Loudspeakers active The second wafer of the switch 46 is required to allow simultaneous energization of the loudspeakers #2 and #3 in selective switch position Z, and also, the selective energization of the single loudspeaker #2, in position Y, immediately prior to energization of both of the loudspeakers #2 and #3.

The switches 41-43, 46, 46 are illustrated as instantaneous make-or-break switches, which so operate that upon engagement of a particular stationary contact by its associated movable contact the loudspeaker associated with the particular stationary contact is fully energized instantaneously. In specific organ systems, particularly those intended to be utilized in religious services, it may be desirable to produce a gradual transition of the music from one loudspeaker or combination of loudspeakers to the next loudspeaker or combination of loudspeakers. Gradual transitional effects may be obtained by utilizing variable resistance switches of the type disclosed and fully explained in U.S. Patent No. 2,215,124, and in the hereinabove referred to U.S. patent to Jordan.

In FIGURE 4 of the accompanying drawings there is illustrated a single wafer of variable resistances switches suitable for utilization in the system of the present invention. A camming switch actuator 101 is slidable upon a shaft 102 and serves to close one switch for each position longitudinally of the shaft. The cam actuator 101 may be controlled manually or by the pedal 48, as desired, selectively to actuate variable resistance switch elements l2 103 aligned parallel with the shaft 102. The switch elements 103 are supported on an insulating wafer 104 and are aligned on the wafer in the direction of movement ofY the actuator 101 along the shaft 102. Each of the switch elements 103 includes a conductive segment 105 in .electrical contact with a strip of resistance material 106. A curvilinear, resilient conductive switch contact 107 is secured to the insulating wafer 104 at a point spaced from the resistor strip 106 and extends over the resistance material 106 to a point above the conductive segment 105. In the open switch position, the finger 107 does not contact the resistance strip 106 or the conductive segment 105. As the actuator 101 progresses from left to right, as viewed in FIGURE 4, the switch fingers 107 are progressively engaged by the cam 101 and are caused initially to engage the resistance strips 106 at one edge thereof, and to roll progressively over the strip 106 and into engagement with the conductive segment 105. The switches initially provide a circuit through a maximum predetermined resistance which is gradually decreased as contact proceeds progressively `along the resistance strip 106, and finally eliminated entirely when contact is made with the conductive segment 105. The actuator 101 may be symmetrical about a center line perpendicular to its path of travel and, therefore, as it proceeds past the full switch closing position, the finger 107 is disengaged from the segment and rolls back over the strip 106, thereby gradually increasing the resistance in the circuit until the circuit is opened. The axial length of the switch actuator 101 may be sufficient, with respect to the spacing between the fingers 106, that two switch elements 103 are actuated concurrently during a portion of each switch actuating interval. More specifically, the resistance in one switch may be decreased as the resistance in the preceding switch is increased. By virtue of the utilization of variable resistance switch elements 102, the signal supplied to any transducer of the present system may be gradually increased to a maximum while the signal to another of the loudspeakers is decreasing, 'and gradually decreased as the signal to the next succeeding loudspeaker is gradually increased. The wafer of variable resistance switches illustrated in FIGURE 4 may be substituted for any wafer of switches 46 and 46', conventionally illustrated in FIGURES 2 and 3. The cam actuator 101 may be elongated sufficiently so that it may simultaneously -maintain closed more than two variable resistance switches, and in the limit may simultaneously maintain closed all the switches of a wafer, the actuated switches being closed in succession, however, as the switchractuator moves. By this expedient, the echo loudspeaker #4 may be initially energized, and the overhead and front loudspeakers sequentially energized thereafter, the sequentially energized loudspeakers being maintained energized. The eiiect attainable is one of gradual increase of acoustic radiation, commencing at one point of a church, and spreading to other points in sequence, the volume of sound at each of the points building up gradually to a maximum.

A modification of the variable resistance switch actuating arrangement of FIGURE 4 is illustrated in FIG- URE 5 of the accompanying drawings, wherein the single cam 101 of FIGURE 4 is replaced by a plurality of cam actuators 108, a different one for actuating each of the variable resistance switches 101. The apparatus of this figure is an adaptation of the switch mechanism disclosed and claimed in U.S. Patent No. 2,576,764 to Raymond P. Mor-k, assigned to the assignee of the present application. Referring specifically to FIGURE 5 of the accompanying drawings, a plurality of cam actuators 108 is arranged along a common shaft 1209. The shaft 109 carries a gear 110 meshing with a rack gear 111 which in turn is driven by the pedal 48 through a Bowden wire 112 or similar mechanical connection.

The cam surface of each cam actuator 108 cooperates with the switch contact 107 of a different variable resistance switch 101, illustrated as disposed below the shaft 109 for the purpose of example only, the switches 103 being arranged perpendicular to the axis of rotation of the shaft 109. The cam actuator 108 may be shaped as illustrated in FIGURE with a switch actuating surface 113 extending over any desired arc of the actuator. By approximately determining the arc of the surfaces 113 and the relative rotative position between the actuator 108, the switch 103 may be successively closed and opened to provide a processional system as illustrated in FIGURE 3, or may be successively closed and maintained closed to provide a system of the type illustrated in FIGURE 2.

While I have referred hereinabove to overhead loudspeakers, and while these may be directly overhead, it is frequently desirable to locate these loudspeakers between ceiling and sidewall, or high on the sidewalls, or in combinations of locations, to suit individual architectural arrangements and space availabilities.

The separate divisions of the organ and the solo channel controlled by switch 14 may be provided with separate expression controls 114, illustrated in FIGURE l of the accompanying drawings as connected between the preampliiier and the cross-over network of each division, as mentioned previously or may include tone modulation elfects, to provide spatial enhancement of tones from a single console output signal.

Although the electric organ acoustical radiation system of the present invention has been described as utilizing frequency range division between sound radiators selectively positioned about auditoria, frequency division is also applicable to systems wherein the sound radiators are mounted wholly within an organ console. By providing frequency range division between a low frequency horn mounted, for instance, on the console fall-board near the pedals, and at will selectable high frequency horns mounted at various locations on the console, great flexibility may be imparted to an organ console to provide enhanced acoustical effects.

While I have described and illustrated one specific example of the present invention, it will be clear that variations of the specific details of construction may be resorted to without `departing from the true spirit of the invention asdelined in the appended claims.

What I claim is:

l. In an electric organ system including an electric organ having great, swell and pedal divisions, and a plurality of solo stops, Vthe combination of a directional high frequency acoustical radiator, means operatively associated with said radiator for applying tones` derived from said solo stops selectively to said directional high frequency acoustic radiator, at least one low frequency acoustical radiator, a separate cross-over network connected in cascade with each yof said pedal, great and swell divisions of said electric organ, said cross-over networks each having `a relatively low frequency output channel and .a relatively high frequency output channel, means connecting -all said relatively low frequency output channels to said at least one low frequency acoustical radiator, a plurality of space distributed relatively high frequency acoustical radiators, and switching connections for selectively connecting said relatively hi-gh frequency output channels at will to selected ones of said space distributed relatively high frequency acoustical radiators'.

2. The combination in accordance with claim l wherein there is further provided means for progressively connecting all said channels sequentially to predetermined combinations of said space distributed relatively high frequency acoustical radiators.

3. An electric sound production system for use with an electric Organ console, `said console including pedal, great and swell divisions, comprising a separate crossover network connected in cascade with each of said divisions, said cross-over networks each having a relatively low frequency output channel and a relatively high frequency output channel, at least one relatively low frequency high efficiency sound radiator, means for coupling all said low frequency channels to said at least one low frequency high eiciency sound radiator, a plurality of space distributed relatively high frequency sound radiators and switching connections for coupling said high frequency output channels selectively at will to at least la selected one of said plurality of space distributed sound radiators.

4. The combination in accordance with claim 3 further comprising means operatively associated with said electric organ console for varying the relatively low frequency energy supplied to said at least one relatively low frequency high eliiciency -sound radiator, and means for selectively controlling said means for varying in accordance with the operation of said means Ifor coupling.

5. The combination in accordance with claim `3 wherein at least some of said plurality of space distributed sound radiators are located in the overhead of a room in distributed space relation. Y

6. The combination in accordance with claim 5 wherein there is further provided means for connecting all s'aid first mentioned relatively high frequency output channels to Selected combinations of said relatively high frequency space distributed sound radiators in succession.

7. The combination in accordance with claim 6 further comprising a variable gain amplifier, means connecting said variable gain amplifier in series circuit with said relatively low frequency output channels and said at least one relatively low frequency high e'iciency sound radiator, and means for selectively controlling the gain of said variable gain amplifier in accordance with the selected combinations of -said relatively high frequency space distributed sound radiators.

8. An electric sound reproduction system for use with an electronic organ console, said console including pedal, |great and swell divisions, means operatively associated with said console for amplifying the signal output of said divisions and means yfor controlling the expression of each of said divisions, the combination of a separate cross-over network connected with each of said ampliers, each of said separate cross-over network having a relatively low frequency output channel `and a relatively high frequency output channel, stop means operatively associated with said organ console for selecting a separate tone from said divisions, a further cross-over network for said separate tone, said further cross-over network having a further relatively high frequency output channel and a further relatively low frequency output channel, `a relatively low Ifrequency high efficiency sound radiator, means for coupling all said low frequency channels to said relatively low frequency high efficiency sound radiator, `a first high frequency sound radiator, means for coupling only said further relatively high frequency output channel to said high frequency sound radiator, a plurality of space distributed relatively high frequency sound radiators, and switching means coupling at least said first mentioned relatively high frequency output channels selectively at will to selected ones of `said plurality of relatively high frequency space distributed sound radiators.

9. The combination in accordance with claim 8 where-- Iin at least some of said plurality of space distributed sound radiators are located overhead in a room in distributed space relation and wherein said means for coupling includes means for selectively coupling said first mentioned relatively high frequency output channels simultaneously to all of said space distributed radiators and includes means for selectively coupling said lirst mentioned relatively high frequency output channels selectively at will to selected space distributed radiators.

l0. The combination in accordance with claim 9 wherein said last mentioned means for selectively coupling further comprises a plurality of variable impedance switch means connected in series circuit with said relatively high 15a frequency output channels and said space distributed radiators.

11. The combination in accordance with claim wherein said last-mentioned means for selectively coupling further comprises means for sequentially and selectively coupling said relatively -ln'gh frequency output channels to said space distributed radiators and wherein means are provided for gradually decreasing the impedance of selected ones of said variable resistance switch means while simultaneously gradually increasing the resistance of selected others of said variable resistance switch means thereby to gradually transfer coupling of said relatively high frequency output channels from selected ones to selected others of said space distributed radiators.

12. The -combination in accordance with claim 8 further cornprising amplifier means connected in series circuit between said relatively high frequency output channels and said switching means.

13. The -combination in accordance with claim 8 further comprising ampliiier means connected in series circuit between said switching means and said relatively high frequency sound radiators.

14. An electric organ having at least two divisions, a crossover network connected to each of said divisions, each of said crossover networks having at least two channels, a low frequency radiator connected to one channel of each crossover network, a plurality of high frequency radiators and an operative connection between each of said high frequency radiators and the second of said channels of said crossover networks, said connections including switching means.

15. The combination according to claim 14 wherein said switching means is arranged for progressively and sequentially connecting said high frequency radiators with said second of said channels in a predetermined order.

16. The combination according to claim 15 wherein is provided operative means for varying the signal amplitude supplied 4to said low frequency radiator from said one channel of each crossover network, said operative means being ganged with said switching means.

17. An electric organ having at least two divisions, a crossover network connected to each of said divisions, each of said crossover networks having at least two channels, a low frequency radiator connected to one channel of each crossover network, a plurality of high frequency radiators and an operative connection between each of said high frequency radiators and the second of said channels of said crossover networks, said connections including switching means, a solo stop channel connected to said divisions, a further crossover network in said solo liti stop channel, said further crossover network having a low frequency and a high frequency output channel, an operative connection 'between said low frequency output channel of said further crossover network and said low frequency radiator, a further high frequency radiator, and an operative connection between the high frequency output channel of said further crossover network and said further high frequency radiator.

18, An electric organ having at least two divisions, a crossover network connected to each lof said divisions, each of said crossover networks including a low fre-k quency out-put channel and a high frequency output channel, low frequency radiator means, circuits connecting all said low frequency output channels to said low yfrequency radiator means, a plurality of high frequency radiators dispersed about a space, and operative connections between said high frequency output channels and said high frequency radiators, said operative connections including switching means.

19. The combination according to claim 18 wherein said switching means is a sequential switch device for connecting said high frequency radiators sequentially in predetermined order to said high frequency output channels.

20. The combination according to claim 19 wherein is further provided means lfor adjusting the volume of sound emanating from said low frequency radiator means in programmed relation to the operation of said sequen-V tial switch device.

References Cited in the file of this patent UNITED STATES PATENTS 1,852,624 Nicolson Apr. 5, 1932 1,877,317 Hitchcock Sept. 13, 1932 1,931,235 Nicholson Oct. 17, 1933 2,017,153 Kellogg Oct. 15, 1935 2,274,199 Hammond Feb.24, 1942 2,298,618 Garitz et al. Oct. 13, 1942 2,382,413 Hanert Aug. 14, 1245` 2,420,204 Sinnen --.May 6, 1947V 2,500,820 Hanert Mar. 14, 1950 2,513,109 Roth June 27, 1950 2,583,566 Hanert Jan. 29,1952 2,778,874 Mueller Jan. 22, 1957 2,821,878 Stibitz Feb. 4, 1958 2,831,069 Snow Apr. 15, 1958 FOREIGN PATENTS 928,351 Germany May 31, 1955 

